changed syntax of :pom-plugins definition for pom task

1. support of [:configuration ... ] was removed
2. it was replaced with map which contains arbitrary XML definitions,
syntax is the same as in pom-additions

3. also added use case in pom-plugins
task pom / :pom-plugins
added backward compatibility with version 2.3.3
Bump version up to 2.3.4-SNAPSHOT.
task pom / :pom-plugins - bug fixed: extra <configuration> tag
Fix 'repl :connect <port>' when used outside of a project [fixes #1344]

connect-string now verifies that the string ends with a port after the
string is fully formed, aborting if no port is found. This also
includes improvements to the repl help text, and more test coverage
for connect-string.
Merge pull request #1345 from tobias/repl-port-abort-fix

Fix 'repl :connect <port>' when used outside of a project [fixes #1344]
More nuanced merging of project defaults.
Merge pull request #1342 from dominikdz/master

changed syntax of :pom-plugins definition for pom task
Merge pull request #1341 from llasram/meta-merge-defaults

More nuanced merging of project defaults.
Account for repl urls with paths [fixes #1344, again]
Mention `lein deps` in the tutorial.

Describe how to use lein to actually install and use a dependency.
Merge pull request #1351 from coventry/more-explicit-instructions-on-installing-dependencies

Mention `lein deps` in the tutorial.
Support nested `do` chains, remove implicit help.

Also provide an example in the sample project. Closes #1359.
Merge pull request #1361 from technomancy/nested-chains

Support nested `do` chains, remove implicit help.
Clarify java compiler not found message. Fixes #1322.
Merge in uberjar profile before implicit aot check

Fixes #1358.
Update dependency name in profile example

It looks like in cab18f6bfeeee0a2808922ca130dd7538b0effda the dependency changed from midje to expectations, but the explanation text still referred to midje.
Merge pull request #1362 from pashields/patch-1

Update dependency name in profile example
Retain whitelisted keys for the eval/prep phase.

fb532b0 reverted this issue back on, because the whitelisted keys were
ignored for the prep phase.

Fixes #770.
Don't print with-profile output when only one profile is invoked.