Import 294 songs from Carmina Leonis PDF

Add import-songs.py script that extracts songs from the PDF text
and generates .tex files with leadsheets format. Adds song
properties for all reference books (BuLiBu, BuLiBuII, CL, SwA,
Barde, LiBock). Generates all-songs.tex with alphabetical inputs.

Note: Chord alignment is approximate from PDF extraction and
may need manual review for some songs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

songs/come-by-the-hills.tex

@@ -0,0 +1,37 @@
+\begin{song}{
+  title = {Come by the hills},
+  lyrics = {Gordon Smith},
+  composer = {traditionelles gälisches Lied “Buachaill On Eirne”},
+  cl = 54,
+}
+
+\begin{verse}
+Co \chord{D}me by the hi \chord{G}lls to the l \chord{D}and / where f \chord{G}ancy is fr \chord{D}ee. \\
+D                 G              fis \\
+And stand where the peaks meet the sky / and the \\
+lo \chord{e}ughs meet the se \chord{A}a / where the ri \chord{D}vers run c \chord{D7}lear and \\
+the br \chord{G}acken is g \chord{D}old in the s \chord{A}un. \\
+Ref.: \\
+And the care \chord{h}s of tomor \chord{G}row must w \chord{D}ait \\
+until t \chord{G}his day is d \chord{D}on \chord{A}e.
+\end{verse}
+
+\begin{verse}
+Come by the hills to the land \\
+where life is a song. \\
+And sing while the birds fill the air \\
+with there joy all day long. \\
+Where the trees sway in time \\
+and even the wind blows in tune
+\end{verse}
+
+\begin{verse}
+Come by the hills to the land \\
+where legends remain. \\
+Where the stories of old fill the hearts \\
+and may yet come again. \\
+Where our past have been lost \\
+and the future is still to be won.
+\end{verse}
+
+\end{song}