Replaced android.test.InstrumentationTestRunner with com.zutubi.android.junitreport.JUnitReportTestRunner.

Create javadoc/ directory when doing "ant javadoc". Fixed installing debug builds with ant.

"ant -f tests/build.xml debug && ant -f tests/build.xml installt test test-report" compiles, installs, tests,
and saves output to tests/junit-report.xml.
removed stylesheets from javadoc target, as not found on cloudbees. they weren't quite right, anyway.
Grouped app-specific and store-specific strings

First step to make it easier to change the branding in forks and support
different app stores.
Changed the translations to match the new grouping in strings.xml
Fixed "errors" in translations

Mostly replacing "..." with ellipsis character "…"
Fixed description of K-9 Mail's delete permission
Removed unused stuff
Changed some strings for esthetical reasons (backport from Kaiten)
Removed date format strings from translations
Create database in a transaction (for performance)

On my emulator, it takes 70ms instead of 250ms.
On a very specific hardware, it takes 0,5s instead of 4,1s.

I willingly did not indent the code between my try/catch (for the patch to be readable).
Fixed a typo
Added test to validate the date format strings in translations
Introduced enum for the MessageCompose actions (compose, reply, ...)
Extracted methods for easier reading
Put the logic that decides which message format to use in one place

This change is in preparation for the future rich text editing
functionality.
Explicitly set the language to be used in unit test
summary: updated build scripts for testing.

.gitignore:
  added files created by new targets.

build.xml:
  removed targets install and reinstall.
  modified target help to depend on android_rules.help and only explain targets defined here.
  updated target javadoc.
  added targets lint-xml, lint-html, and monkey.
  added private target -pre-clean to remove files created by new targets.

tests/AndroidManifest.xml:
  updated note on running the tests.

tests/ant.properties:
  removed test.runner as target test is now overridden.

tests/build.xml:
  removed target test-report as it is now integrated with overridden target test.
  overrode target test to disable deleting coverage.em and use the new test runner.
  overrode target help to depend on android_rules.help and only explain targets defined here.
  added targets javadoc, lint-xml, lint-html, and artifacts.
  added private target -pre-clean to remove files created by new targets.

tests/clean-tests.sh:
  new sh script to run through all the tests.
Create an HTML version of text/plain-only drafts in the database

Without this, text/plain-only messages with K-9 Mail's "identity header"
are displayed as "No text" (when moved out of the Drafts folder).
Fixed loading messages from the database when message format is AUTO
summary: updated build.xml and tests/build.xml.

build.xml and tests/build.xml:
  updated general format to match what is generated in a new project.
  moved targets common to both to build_common.xml.
  replaced some exec calls (perl, mv) and inline javascript with ant tasks (including extensions from Android and ant-contrib).

build.xml:
  fixed indentation.
  privatized targets that don't need to be called directly from command-line.
  renamed some properties.

tests/build.xml:
  renamed test project from K9 to K9Tests.

tools/ant-contrib.jar:
  new!

.gitignore:
  added note about local per-repo rules.