NPE fix in default branch determination & NPE fix when commit cache contains removed repo

This is a normal condition that complicates debugging, i.e.
when catching all NPE's.

Add the commons-io library explicitly to the depencencies.
It was already present as a transitive dependency but is now used in code.
Using the version 2.2 as that got so far already packaged in ext.

Implement adjusting file and directory permissions for shared
repositories in JGitUtils.

Implement the methods getFilemode and setFilemode
in JnaUtils. Not using the libc names as we don't
necessarily use JNA and because it is not necessarily
a one to one mapping.

repository as if it was created with the --shared command line switch of git.

Set the user repository name space from settings when starting Gitblit.

Gather logic for building the path/name of a personal user repository into one class.

Close streams in finally block.

Maintain repository 'description' file.

Close input and output streams in a finally block so that they do not linger around and occupy system resources when an exception occurs.

Make use of the 'description' file in Git repositories which is used by tools
like gitweb or cgit and often by standard hooks. Update the file when changing
the description and initialize the Gitblit description from the file when
Gitblit reads a new, existing repository.

Add a new class, HtpasswdUserService, which performs authentication
against a text file created with the Apache 'htpasswd' program.

Added dependency on commons-codec:1.7

Add setting to cap number of activity days to display

This patch adds a setting, 'web.activityDurationMaximum', that specifies the
maximum number of days of activity that may be requested. The default value is
30. When the number of days requested exceeds this value, the request is
handled as though the maximum value was requested.

MyDashboard page bugfix for project links

Problem:
In version 1.3.1, on the MyDashboard page, in the "projects" tab, the project name html links listed in the section are formatted wrong; they are missing the ?p= parameter. Clicking on those links redirects back to the home page (MyDashboard).

What did I expect:
To be taken to the repositories page for the project I clicked.

What code needs to change:
FilterableProjectList.fm at line 9, needs to add the ?p= url parameter.
I'm basing this on how the WicketUtils.getProjectName(PageParameters params) method works at line 457 and logic in ProjectPage.java at lines 95-98.

Although explicitly changing the url to include the query param 'p' is a simple fix, based on what I read about in GitblitParamUrlCodingStrategy and its parent class MixedParamUrlCodingStrategy, it would seem that the url path "/project/foo" should end up adding a request parameter "p=foo" as setup in GitBligWebApp line 141: mount("/project", ProjectPage.class, "p"); However, I'm not familiar with Wicket and don't have Gitblit setup locally to build and run, so not able to debug further.